Knowledge is a justified, true, belief.

Plato's definition of knowing In order for someone to know a proposition, the proposition has to be justified, the proposition has to be true and someone has to believe the proposition is true.

Impersonal Propositional Knowledge- Knowledge be description.
Personal Knowledge- Knowledge by conviction. Knowledge by inraspection /introspection. Knowledge by Acquaintance. Knowledge by practice.
Subconscious Knowledge- Knowledge by instinct.

How to justify your belief:
Correspondence theory- Comparing with facts of senses, experience and logic
Coherence Theory- By having a definition
Pragmatic Theory- Your personal thoughts. What you know, that can justify your belief.

Truth test, PIE:
Public
Independent
Eternal

If all these can be answered as "yes" then there is a universal truth

Ways of Knowing (WOK)

Perception of senses
Emotions
Reasoning
Language
Logic
Authority
Experience

Areas of Knowing (AOK)

Natural Science
History
Art
Ethics
Maths